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Toxicology Committee Annual Reports

NAMA Toxicology Committee Report for 2007
Recent Mushroom Poisonings in North America

By Michael W. Beug, Ph.D., Chair NAMA Toxicology Committee

The 2007 mushroom season produced very few reports of mushroom poisoning which was a marked relief after 2006 which saw numerous serious poisonings. There were 29 reports involving 45 people poisoned plus 10 reports involving 12 dogs poisoned. There was one human death questionably attributed to mushroom poisoning and three dog deaths attributed to unknown mushrooms. There were also numerous reports of ingestion of mushrooms by young children where there were no symptoms, but only one of those has been included as an example.

Marilyn Shaw continued her close work with the Rocky Mountain Poison Center and contributed over half of the total reports cited herein. Another significant group of reports came from Jan Lindgren and Judy Roger who work with the Oregon Poison Center and a group of volunteers, mostly from the Oregon Mycological Association. Even though the number of cases was small, there were some very interesting things to be learned.

There were 5 cases involving intentional ingestion of psychoactive mushrooms that went badly. The mushrooms involved were either Psilocybe cubensis or Amanita muscaria both of which can easily be purchased and both of which can also easily have been adulterated. The most serious case involved a healthy 26 year old man who consumed up to six or seven 3"-4" specimens of a "red mushroom with white spots," obviously Amanita muscaria. Marilyn Shaw reports that she was told that two hours post ingestion he was sweating had flushed skin and slurred speech. He went to bed. Two hours later his girl friend awakened him but he was uncoordinated and could not walk. He went back to sleep. The next morning he was found dead. There was less than 12 hours elapsed between ingestion and death. A post-mortem drug screen for 2,000 drugs turned up nortryptyline and Marilyn believes acetaminophen, but nothing else. No direct cause of death was found so the coroner attributed the cause of death to Amanita muscaria. In the very few deaths from Amanita muscaria over the past 100+ years that we have been able to uncover, death has been from indirect causes like hypothermia or aspiration of vomit while in a coma-like sleep and not from direct toxicity. With such a large ingestion it is possible that there was enough muscarine to be a contributing cause – muscarine was first discovered in Amanita muscaria but it is a trace constituent. Both Marilyn Shaw and I have read extensively on Amanita muscaria, including the rare book Mushrooms, Russia and History by R. Gordon Wasson and Valentina Pavlona Wasson and we agree with their observation that Amanita muscaria "inebriates, it does not kill." However, unlike the high from psilocybin and psilocin in some mushrooms, the high from Amanita muscaria is one that few people would want to experience twice. Amanita muscaria is a dangerous and lousy recreational drug. Of the many users of mushrooms that I have interviewed, I have only talked to two who thought that the experience was one that they would ever repeat. There is a very narrow dose-response curve with Amanita muscaria (and Amanita pantherina) and it is very easy to completely lose muscular coordination and possibly freeze to death if you are out in the cold or vomit and aspirate your vomit with possibly lethal results. There is a deep coma-like sleep that soon follows any meaningful ingestion. Expensive hospitalizations are the norm after use of either Amanita muscaria or Amanita pantherina.

Another serious case of mushroom poisoning involved the ingestion of Amanita smithiana in a meal of three mushrooms which were mistaken for White Matsutake, Tricholoma magnivelare. Judy Roger identified part of a stipe base of A. smithiana and what appeared to be part of a Tricholoma focale from old trimmings left from the mushrooms. There is no evidence as to the identity of the third mushroom. The onset of symptoms began about 5 hours after the meal and the victim experienced acute renal failure with hepatic involvement. He was hospitalized for 5 days and outpatient dialysis was required after he left the hospital. Toxicologists at Oregon Health Sciences University concluded that since the liver was involved, the victim must have eaten Amanita phalloides. This is highly unlikely as he wasn't in an area where Amanita phalloides grows, it was too early in the season for A. phalloides, and very few of this species were found this season. Confidentially laws prevent us from getting complete details about the case, but plans are for the OPC staff to publish a report on this case.

There were two very different cases including Amanita species known as "Death Caps" and as "Destroying Angels." In the first case the victim in New York State consumed mushrooms in the Amanita virosa complex. Bill Bakaitis did the identification and performed the Meixner tests, the first of which was negative though additional testing revealed a weak positive result – much weaker than Bill had seen in previous work with this species. That may well account for the fact that the victim experienced just GI distress and blood work that was "abnormal, not too bad." In the second case a California artist was making a 20"x30" art piece composed of successive spore prints of Amanita phalloides. She was doing the spore prints indoors and after some time developed sensitivity to the spores, experiencing a sore throat and cold-like symptoms. She could feel the effects begin in her throat as she worked with the mushrooms. Her partner developed a similar sensitivity. It is not unheard of for people working with mushrooms in closed environments to experience adverse effects from inhaling spores, even when the species are edible.

Marilyn Shaw also reported a number of adverse reactions to Leccinum species, including Leccinum insigne. She has now seen enough of the cases to realize that this is another species with delayed onset of symptoms — typically about 6 hours. The symptoms are gastro intestinal distress which can be severe. In one incident, several individuals at a mushroom foray became ill after the formal mushroom tasting event. One person at the event initially thought that the culprit dish (of about 15 dishes served) was the Russula xerampelina that may have had a toxic Russula mixed in that would cause significant gastric distress — but later agreed that the delayed onset pointed elsewhere. There was also a dish containing Leccinum species and the timing of the onset of symptoms in the five known victims pointed Marilyn Shaw clearly in the direction of the dish with "Orange Aspen Boletes," in short, Leccinum.

Reports of poisoning by Boletes with red tube mouths are quite rare. Some red-tubed species do have a nasty reputation but it has never been clear which species are the problem. Unfortunately, even with two incidents this year involving a total of 6 people, we are no closer to an answer. In both incidents the culprit was identified as Boletus satanus but neither incident involved positive identification of the mushrooms consumed — all we know for sure is that they were Boletes with red tube mouths growing in California and in one case the associated trees were oaks. In both cases the GI distress was exceptionally severe, putting five of the six in the hospital. In one individual the blood turned a striking bright red.

The pattern of increased interaction between mycologists and veterinarians has lead to continued reporting of dogs ingesting mushrooms. Clearly some dogs will ingest mushrooms again and again, getting sick again and again. Mushrooms that are generally not lethal to humans, e.g. Scleroderma species and Inocybe species can kill dogs. Dogs also consume the "Destroying Angel" mushrooms with often lethal results. This year three dog deaths were reported from the Pacific Northwest. Unfortunately, there was no vomitus or fresh mushrooms available to identify the culprit. In two cases where the dog survived, Judy Roger was able to identify chunks of mushroom thrown up by the dogs – one case involved Paxillus involutus and the other involved the Scleroderma cepa group.